A control unit for determining an incident intensity of a light source in a bio-analvte device and a method thereof

Complete Specification:

The following specification describes and ascertains the nature of this invention and the manner in which it is to be performed.

Field of the invention

[0001] This invention is related to a control unit for determining an incident intensity of a light source in a bio-analyte device and a method thereof.

Background of the invention

[0002] An accurate monitoring of bioanalyte levels in patients is vital to a patient's health. Monitoring of glucose in blood sample of diabetic patients, for example, is valuable in order to prevent blindness, kidney diseases, necrosis of nerve tissue, as well as other complications. On a broader basis, it has become increasingly important in analytical and clinical chemistry to have the capability of remote (or noninvasive) sensing of chemical and physical parameters. Some methods of performing this type of sensing is known in the state of the art, such as potentiometry, amperometry, Pulse Oximeters, Continuous Hb monitors. In addition to these methods, optical techniques can be used for remote sensing of analytics and other substances. [0003] A prior art document IN201841005410 discloses a controller to determine incident intensity of a light source for a hemoglobin monitoring device. The controller adapted to supply a reduced rated power to at least one light source, when the device is switched ON, the rated power is reduced by a predetermined factor. The control unit measures a value of the incident intensity of emitted light from the at least one light source through a photodetector. The control unit further determines the incident intensity by multiplying the measured value with the predetermined factor.

Brief description of the accompanying drawings

[0004] Figure 1 illustrates a control unit in a bio-analyte device, in accordance with an 25 embodiment of the invention; and

[0005] Figure 2 illustrates a flowchart of a method of determining an incident intensity of a light source in a bio-analyte device in accordance with an embodiment of the invention.

Detailed description of the embodiments

[0006] Figure 1 illustrates a control unit for determining an incident intensity of a light source in a bio-analyte device in accordance with an embodiment of the invention. The bio analyte device 10 comprises a photo detector 14 and a fdter element 16 positioned between the light source 12 and the photo detector 14. The light source 12 comprises at least one light element 13. The control unit 11 receives a current value and an amplifier gain corresponding to each of the light element 13 of the light source 12 from a communication device 18. The control unit 10 calculates a light intensity corresponding to each of the light element 13 of the light source 12, from corresponding received current value and received amplifier gain. The control unit 11 computes an actual current multiplication factor and an actual gain multiplication factor from the calculated light intensities. The control unit 11 further determines actual incident intensity of light source from the actual current multiplication factor and the actual gain multiplication factor.

[0007]Further, the construction and working of the control unit 11 and the components of the bio-analyte device 10 is explained as follows. The filter element 16 that is chosen from any one of the following filter elements comprising a neutral density filter and a color graduated filter is positioned between the light source 12 and the photo detector 14. The light source 12 comprises at least one light element 13 and the light element 13 being a light emitting diode (LED) according to one embodiment. However, the type of light element 13 is not restricted to LED but can be any other type of light element that is known to a person skilled in the art.

[0008]According to one embodiment of the invention, the light source 12 comprises four light elements 13 i.e., two sets of light elements 13 ( first set of light elements 13 (a) and a second set of light elements 13(b) and according to another embodiment, the light source comprises two light elements 13. The incident intensity detected from the photo detector 14 is used to determine at least one human body parameter.

[0009] The human body parameter is chosen from any one of the following Hemoglobin, creatinine, red blood cell count, white blood cell count, platelets, vitamin D, thyroid components and the like. For instance, to determine Hemoglobin (Hb) in a human body, the device 10 is designed with four light elements 13, wherein to determine saliva characteristics, the design is designed with two light elements 13. The list of the human body parameters are not restricted to the above-mentioned parameters, but can be any other parameter that is known in the state of the art.

[0010]The control unit 11 that process the detected light intensity from the photo detector 14 is chosen from a group of control units comprising a microprocessor, a micro-controller, an integrated chip, a digital circuit and the like. According to one embodiment, the control unit 11 as mentioned above is the control unit 11 of the bioanalyte device 10. According to another embodiment, the control unit 11 is present in the communication device 18 of the user. The control unit 11 in the communication device 18 of the user receives the detected incident intensity of the light from the photo detector 14 of the device 10 and processes it further to determine the actual incident light intensity.

[001 l]The communication device 18 is chosen from a group of communication devices comprising a smart phone, a person digital assistant, a computer and the like. The communication device 18 comprises a mobile application that is used to alter /change the current and the amplifier gain values for each of the light element 13 of the light source 12. The current and the gain values that are set by the user in the mobile application of the communication device 18, is transmitted to the control unit 11 of the device 10. The control unit 11 upon receiving the set current and the gain values of the each of the light element 13, supplies the corresponding current to the each of the light element 13 of the light source 12.

[0012] The current received by the control unit 11 for each of the light element 13 is a reduced current that is modified by a predefined factor. For instance, the user sets the current in the mobile application as 2.5 A instead of 5 A and the same is transmitted to the control unit 11. The control unit 11 upon receiving the 2.5A value, supplies the same amount of current to at least one light element 13. For instance, if the light source 12 comprises four light elements 13, the control unit 11 receives four current values and four amplifier gain values from the communication device 18 of the user. Let the current values and the amplifier gain values received are II, 12, 13, 14 and Gl, G2, G3, G4.

[0013] According to one embodiment of the invention, the received current and the amplifier gain values are set different to each of the light element 13. According to another embodiment of the invention, the amplifier gain value is set as same for first two light elements 13 (a) and the current value is set as same for next two light elements 13(b) i.e., Gl and G2 has the same value and 13 and 14 has the same value. [0014]In the above-disclosed arrangement, the control unit 11 is adapted to switch ON only one of the light element 13 at a time, by suppling corresponding received current and the amplifier gain. During this time, the other three light elements 13 are in the OFF state. The filter element 16 positioned between the light source 12 and the photo detector 14 is used to allow only a predefined wavelength range of light towards the photo detector 14. For instance, the predefined wavelength range is 400nm-1200nm.

[0015] Each of the light element 13 of the light source 12 has a different range of wavelengths during the operating condition. The filter element 16 allows only the predefined wavelength range during the operating conditions of the device 10. As mentioned above, the filter element 16, which is neutral density filter, is made of a glass with a coating that allows only a predefined wavelength range.

[0016] Figure 2 illustrates a flow chart of a method of determining an incident intensity of a light source 12 in a bio-analyte device 10 in accordance to the present invention. The device 10 comprises a photo detector 14 and a filter element 16 positioned in between the light source 12 and the photo detector 14. The light source 12 comprises at least one light element 13. In step S 1, a current value and an amplifier gain corresponding to each of the light element 13 of the light source 12 are received from a communication device 18.

[0017]In step S2, a light intensity of each of the light element 13 of the light source 12 is calculated from corresponding received current value and received amplifier gain. In step S3, an actual current multiplication factor and an actual gain multiplication factor is computed from the calculated light intensities. In step S4, actual incident intensity of the light source is determined from the actual current multiplication factor and the actual gain multiplication factor.

[0018]The above-disclosed method is explained in detail. Let the light source 12 comprises four light elements 13 (for an example, let us consider the light element is a LED) for calculating a human body parameter like hemoglobin (Hb), the four LED’s 13 are divided into two sets of LED’s .A first set 13 (a) of (LI, L2) and a second set 13(b) of LED’s (L3, L4). The control unit 11 receives four current values and four amplifier gain values from the mobile application that are set by the user of the device 10. The user sets a reduced current value and is transmitted to the control unit 11 of the device 10 through the communication device 18.

The four current values are II, 12, 13 and 14 and the four amplifier gains are Gl, G2, G3 and G4 for corresponding four LED’s LI, L2, L3 and L4.

[0019]Each of the LED 13 receives the corresponding current value from the control unit 11 during an operating condition. E.g., the control unit 11 supplies II for switching ON the LED LI and filter element allows the predefined wavelength range. The photo detector 14 detects/measures the light intensity of the LI LED and the control unit 11 30 amplifies the detected light intensity using the amplifier gain Gl value.

[0020] The control unit 11 calculates the light intensity of LI LED as LGIT1. The same process is adapted in calculating the second LED L2, light intensity LGIT2. In this case, the amplifier gain is maintained constant for both the LEDs’ LI and L2 and the current values are modified. I.e., II is set different from 12 and Gl and G2 are set at the same values.

[0021]The control unit 11 supplies the current 13 to the LED L3 and the photo detector 14 detects the light intensity of the LED L3. The control unit 11 calculates the light intensity of LED L3 by amplifying the detected light intensity of L3 with the amplifier gain G3. The calculated light intensity of LED L3 is LGIT3. The above- disclosed process is adapted in calculating the light intensity of LED L4 from 14 and G4. The calculated light intensity of LED L4 is LGIT4. In this case, the control unit 11 maintains a constant current value and modifies the amplifier gain values, i.e., the user of the device 10 sets G3 and G4 as different values, 13 and 14 as same values.

[0022]The light intensities of first set 13(a) of light elements (LGIT1 & LGIT2) are used to compute the actual current multiplication factor and the light intensities of second set 13(b) of light elements (LGIT3 & LGIT4) are used to compute the actual gain multiplication factor. From the above computed actual current multiplication factor and the actual gain multiplication factor, the control unit 11 determines the actual light incident intensity of the light source. [0023] The above-disclosed process is used during the calibration process of the device

10 and a calibration tool 20 (which is a holder) is used to hold the filter element 16 in the device 10. The determined light incident intensity is stored in the control unit 11 of the device 10 and is used to determine at least one human body parameters during the real-time operation of the device 10.

[0024]With the above-disclosed method, the gain offset variations in the amplifier can be reduced. The usage of the holder 20 and the filter element 16 provides a cost-effective, low- maintenance solution as it does not involve any of the complicated or large components. An accurate intensity of light is calculated using this method, thus increasing the efficiency of the device 10 during the real-time operating conditions. The errors in the light intensity of the light source 12 is reduced using the above method.

[0025]It should be understood that embodiments explained in the description above are only illustrative and do not limit the scope of this invention. Many such embodiments and other modifications and changes in the embodiment explained in the description are envisaged. The scope of the invention is only limited by the scope of the claims